One of the reasons that modern engines have longer life and greater reliability is that their crankshafts are stiffer, are better supported, and fully counterweighted. Compared to a Model A engine crankshaft, the crankshaft in a modern four cylinder engine has larger diameter shorter bearings, a main bearing on each side of every cylinder (5 mains), and a fully counterweighted crankshaft with two equal counterweights for each cylinder. This engineering study and redesign features a 5 main crankshaft, larger diameter short bearings, and full counterweights.

Another reason is that with modern engineering, parts in dynamic environments can be optimized through the use of Solid Modeling and Finite Element Analysis